86 lines · c
1#ifndef _CRYPTO_GCM_H2#define _CRYPTO_GCM_H3 4#include <linux/errno.h>5 6#include <crypto/aes.h>7#include <crypto/gf128mul.h>8 9#define GCM_AES_IV_SIZE 1210#define GCM_RFC4106_IV_SIZE 811#define GCM_RFC4543_IV_SIZE 812 13/*14 * validate authentication tag for GCM15 */16static inline int crypto_gcm_check_authsize(unsigned int authsize)17{18 switch (authsize) {19 case 4:20 case 8:21 case 12:22 case 13:23 case 14:24 case 15:25 case 16:26 break;27 default:28 return -EINVAL;29 }30 31 return 0;32}33 34/*35 * validate authentication tag for RFC410636 */37static inline int crypto_rfc4106_check_authsize(unsigned int authsize)38{39 switch (authsize) {40 case 8:41 case 12:42 case 16:43 break;44 default:45 return -EINVAL;46 }47 48 return 0;49}50 51/*52 * validate assoclen for RFC4106/RFC454353 */54static inline int crypto_ipsec_check_assoclen(unsigned int assoclen)55{56 switch (assoclen) {57 case 16:58 case 20:59 break;60 default:61 return -EINVAL;62 }63 64 return 0;65}66 67struct aesgcm_ctx {68 be128 ghash_key;69 struct crypto_aes_ctx aes_ctx;70 unsigned int authsize;71};72 73int aesgcm_expandkey(struct aesgcm_ctx *ctx, const u8 *key,74 unsigned int keysize, unsigned int authsize);75 76void aesgcm_encrypt(const struct aesgcm_ctx *ctx, u8 *dst, const u8 *src,77 int crypt_len, const u8 *assoc, int assoc_len,78 const u8 iv[GCM_AES_IV_SIZE], u8 *authtag);79 80bool __must_check aesgcm_decrypt(const struct aesgcm_ctx *ctx, u8 *dst,81 const u8 *src, int crypt_len, const u8 *assoc,82 int assoc_len, const u8 iv[GCM_AES_IV_SIZE],83 const u8 *authtag);84 85#endif86